SCIENTIFIC AND TECHNICAL JOURNAL «RADIO COMMUNICATION THEORY AND EQUIPMENT» ISSUE 2, 2007

**A TENSOR APPROACH TO SOLVE THE OPTIMAL ROUTING PROBLEM IN INFORMATION NETWORKS**

*V.I. PARFYONOV, S.V. ZOLOTARYOV*

A new algorithm is proposed to solve the optional routing problem based on applying Kirkhhoff's laws to information networks. The algorithm does not require necessarily to use derivatives of objective functions so that it is very comfortable with distributed realizations. Convergence of the method is justified by drawing on the analogy between informational and electrical networks. In order to realize the algorithm it is proposed a tensor approach of network analysis. It is shown that the application of that algorithm requires a small number of iterations and it is quite acceptable for realizing optimal routing in data communications network.

**RECEPTION OF PHASE-SHIFT SIGNALS RADIATED BY A MOVING SOURCE THROUGH QUADRATURE RECEIVER WITH AN INPUT BANDPASS FILTER**

*G.S. NAKHMANSON, G.A. BAKAYEVA*

Output effect of quadrature correlation receiver during reception of phase-shift broadband signal from a moving source and when there is a bandpass filter on the receiver input is considered. Dependence of cross-correlation function (CCF) complex envelope for CCF of both received and reference signals on delay time, frequency tuning of the received signals in respect to the reference signal and the bandwidth of input filter is analyzed. Also the transformation of time scale for the input signal envelope depending on the transmitter movement is examined.

**ANALYSIS FOR ENERGETIC DETECTION OF BROADBAND SIGNALS WITH POLARIZATION CODING**

*V.V. LIVENTSEV*

An optimal algorithm for detecting phase-shift broadband signal with orthogonally circular polarization coding under known laws of retuning both polarization parameters and signal elements phase has been considered. Generalization of broadband energetic detector circuit fro stochastic vector signal is conducted. It is shown that the polarization coding application in communication systems with phase-shift broadband signal increases the energetic security of such signals without additional operating frequency band in conditions of a priori indetermination at the receiving side.

**INFORMATION RATE ESTIMATION UNDER CONDITIONS OF NOISE INTERFERENCE WITH ERROR CORRECTION CODES **

*A.P. VARIN*

The possibility to increase average information rate in conditions of noise interference at the expense of adaptive changing code redundancy is considered.

**COMPUTER SIMULATION OF ELECTROMAGNETIC COMPATIBILITY BODIES**

*A.D. KOROBOVA, E.A. KHROMYKH*

Practical implementation of three-dimensional virtual structures (electromagnetic compatibility bodies) intended to do analysis of electromagnetic environment produced by a group of radioelectronic facilities by means of the computer mathematics MathCad is studied.

**IMITATION MODEL FOR ESTIMATED PROBABILITIES OF RIGHT AND FALSE DETECTION IN SEARCH DEVICES**

*V.V. MAYOROV*

With the aid of MathCad packet an imitation model of phase-shift noise-like signal search device is developed. Detection probabilities of the latest patent search devices for a sequence length L = 31 are estimated.

**PUNCTURING MATRIX OPTIMIZATION IN RADIO ENGINEERING SYSTEMS WITH TURBO-CODES**

*A.M. BOBRESHOV, HOANG THU HA*

Theoretical and practical approaches for puncturing algorithm of turbo-code are considered and principles of constructing optimal structure of puncturing matrix for turbo-code are determined. The modeling has been conducted simulation which proved the assumed principles of optimal structure determination for puncturing matrix.

**ANALYSIS OF ASYMPTOTIC PRESENTATIONS FOR COMPLEX PROBABILITY INTEGRAL**

*N.E. KOROTKOV*

Simple and comfortable in use asymptotic presentations for complex probability integral at argument approach to infinity are received and their properties are analyzed. Features for employment of such presentations complying with these properties are defined.

**STABILITY ANALYSIS OF A PARAMETRIC CIRCUIT BY SPECIAL LIAPUNOV METHOD**

*YU.B. NECHAEV, N.D. BIRYUK, E.V. LATYSHEVA*

A sequential oscillating circuit with periodically time variable positive elements is considered. A free process equation is presented which is reduced to its more common case than Mathiew’s one. The circuit stability analysis by Liapunov method is proposed specially developed for truncated linear differential equation of second order with periodical positive coefficient.

**INTERFERENCE FRACTIONABILITY DECREASE WAYS IN SYNTHESIZERS ON PULSED AUTOMATIC PHASE CONTROL WITH DELTA-SIGMA MODULATORS IN FRACTIONAL FREQUENCY DIVIDERS**

*S.K. ROMANOV, I.A. MARKOV, N.M. TIKHOMIROV*

Variants of interference fractionability decrease ways in pulsed automatic phase control are quantitatively evaluated with delta-sigma modulators: using a linear pulse-phase detector of type called the “sampling-storing”, decreasing noise level with phase modulator in a reference channel, interference compensation by means of an additional circuit on the phase detector output with charge pumping.

**REVIEW OF MOBILE ECM COMPLEXES AND SHORTWAVE ANTENNAS EMPLOYED**

*YU.B. NECHAEV, V.I. NIKOLAYEV, YU.G. PASTERNAK, I.V. POPOV*

Review of mobile and transportable multiband systems capable to suppress communication in short-wave band is given as well as that of shortwave antennas of produced by the largest firms. The conclusion about urgency of research effectiveness for existing and development of new shortwave antennas for application in new ECM systems is drawn.

**LOOP AND DIPOLE ANTENNAS MODELING TAKING INTO ACCOUNT INFLUENCE OF UNDERLYING SURFACE**

*YU.B. NECHAEV, V.I. NIKOLAYEV, YU.G. PASTERNAK, I.V. POPOV*

Estimation of efficiency for loop and dipole antennas mounted in a car of “Vodnik” type taking into account influence of underlying surface is carried out. Modeling results enabled to make the conclusion that in case of underlying surface with high conduction an underlying antenna supports a higher energetic potential of ECM system.

**CALCULATION OF MULTI-STAGE LIGHTNING-DISCHARGE PROTECTION OF RADIO CENTERS ANTENNA-FEEDER DEVICES **

*V.I. GRISHCHUK, L.B. GERASIMENKO, I.P. DUBROVSKY, G.V. PODSHIVALOVA*

The data about thunder effect on paths of common antenna-feeder device in HF band are given, circuit engineering decisions as to increasing resistance of equipment to these effects are discussed, effectiveness estimation of the proposed multi-stage lightning-discharge is considered.

**RETURNED MATCH-FILTERING DEVICE**

*G.E. KUSHCHEV, A.N. KONCHAKOV, YU.YA. YAKOVENKO*

Building a narrow-band returned match-filtering device (RMFD) is considered for broadband antennas with high SWR value. RMFD advantage in comparison with cascade connection of returned matching device and filter, each of which has only proper function, is shown. Methods, example of calculation and recommendations concerning practical realization of RMED are presented.

**APPROACH FOR DATA COMMUNICATION SYSTEMS EFFICIENCY ESTIMATION BY RADIO CHANNELS**

*V.A. MAKOVIY, D.V. AKSENOV*

Approach for quantitative evaluation for different data communication systems efficiency estimation has been studied. Taking as an example a simple data transmission protocol a technique of data communication efficiency estimation is considered. It is conducted as per communication channel efficiency indicator.

**DISCRETE SPECTRUM COMPUTATION AND SHORT PROCESS APPROXIMATION IN TERMS OF ITS PRESENTATION AS A SUM OF NONORTHOGONAL HARMONIS**

*E.V. DMITRIEV*

A new qualitative characteristic of short processes begins to be considered, that is spectrum consisting of a final optimal set of non-obligatory orthogonal harmonic components. These spectrum properties are described. The conclusions about decomposition possibility of discrete and continuous processes in final harmonic series are made. Methods of effective approximations for short processes used during computation of a new spectrum are described.

**DETERMINATION OF DISCRETE SPECTRUM PARAMETERS AND TRENDS FOR WAVED PROCESSES OF FINITE DURATION**

*E.V. DMITRIEV*

A manner of analytic determination for spectrum and nonlinear trend of discrete in-time process is described. The manner is based on its representation by the power polynomial sum and a set of sine-form terms, using their properties and applying the method of the smallest squares for finding the searched parameters.